Classifier



July 20, 1943.

P. L WIGTON CLASSIFIER Filed Dec. 24, 1940 INVENTOR. PAUL 1.. nus 70ATTORNEYS,

Patented Jul 'zo, 1943 UNITED'STATES PATENT OFFICE' Paul L. Wigton,Denver, 0010., assignor to Morse vBros. Machinery Company, Denver,0010., a

limited partnership A Application December 24, 1940, Serial No. 371,544

"Claimsf (01. 209-464) This invention relates to improvements inclassifiers of the type having an angularly inclined spiral.

As is well knownto those skilled in. the art, this type of classifierordinarily comprises a tanklike structure in which is formed a pool ofore pulp, and an upwardly inclined trough associated therewith. Aninclined shaft is positioned along the trough and extends intothe pooland carries a spiral which when rotated, moves the settled sands fromthe pool upwardly along the trough to a sand discharge adjacent theupper end of the trough. Means are provided for so rotating the shaftand the spiral, and a particular problem has been the journalling of theshaft, especially the lower end thereof which is submerged in the pool.

Since this pool of pulp contains ground ore of various sizes mixed withwater, the bearing that journals the shaft in the pool is liable tobecome fouled with gritty abrasive material and is difficult tolubricate. Bearings as ordinarily used for the lower end of such ashaft, are not readily accessible for servicing and have been a sourceof trouble.

Furthermore, it is desirable in a classifier of this kind to providemeans whereby the spiral can automatically raise, within certain limits,to avoid breakage in case a foreign object such as va tool, a piece ofsteel or the like, should inadvertently get into the device.

Therefore, it is an object of the present invention to provide means forjournalling the inclined shaft of a spiral type classifier, which willpermit the spiral to move slightly to avoid foreign matter that mayinadvertently get into the tank. i j

Another object is to provide means for journalling the lower end of theinclined shaft, that overcome the difficulties hereinbefore enumerated,in that said journalling means are" not subject to damage by abrasionand they areeasy of access and easy to lubricate.

Other objects and advantages reside in details of design andconstruction which will be more fully disclosed in the followingdescription and in the drawing wherein like parts have been similarlydesignated and in which:

modified form of the general mechanism shown inFig'ures 1 and 2. l

In order to disclose a reduction to practice of the present inventiveconcept, the accompanying'drawing, which is made a part hereof, will bedescribed in some particularity. The drawing illustrates the inventionas it would be used with a classifier which represents a desirableadvance in the classifier art; however, it will be manifest that theinvention could be used in connection .with other devices where similarbearing and journalling problems exist. Therefore, the presentdisclosure should not be construed to express or to imply anylimitations to the invention, the scope of which is, in reality,measured by the appended claims.

In the drawing, reference character 5 denotes the pool-forming tankportion of a typical classifier, with which is associated an upwardlyinclined trough 6. A shaft 1 is journalled ad-. jacent the aforesaidstructure and at an incline with reference to the horizontal, andcarries a spiral 8 which is positioned and adapted to move settled sandsup out of the pool formed in the tank portion 5 and up along the troughV6 to a sand discharge 9.

The shaft 1 is provided with a so-called selfalining bearing Illadjacent its upper end, which bearing permits a limited angular movementof the shaft. w

Suitable gearing I2 is associated with the upper end of the shaft torotate it at a desirable speed and in all of its normal angularpositions, which positions will vary only a few inches at the lowerendof the shaft, thus requiring relatively small latitude of movement atthe upper or end thereof is a sheave l3 and journalled thereabove is asecond similar sheave l4 carried in bearings 15 and I6.

, -An endless chain I! is reeved about the sheaves I3 and M whichpreferably are provided with ridges and depressions in their grooves tofit the links of the chain so that no slippage may occur between thechain and either sheave I3 or M.

It is readily manifest that the lower end of the shaft is thus suspendedand journalled for rotation in a highly desirableamanner. There aresubstantially no sliding frictional surfaces within the pool formed inthe tank portion 5, since the lower end of the shaft is, in reality,carried in bearings l5 and I6 entirely above and out. of the pool wherethey cannot be contamie nated by grit in the pulp and where they areconveniently accessible and easily lubricated.

At the lower end of the tank a removable housing l8 may be provided,which surrounds the lower end (a of the inclined shaft 7. This lower end1a of the shaft may be provided with a protecting cap H! which ispositioned within the housing IS. The relationship of the interiordimensions of the housing l8 to the exterior size of the cap I9 is suchthat said cap I9 does not ordinarily come in contact with the inner surfaces of the housing l8 because clearances are provided. However, sincethe housing I8 is greater in its vertical dimension than in itshorizontal dimension, the shaft 1 inclusive of the cap I9, may raise afew inches to avoid breaking if a foreign object inadvertently gets intothe tank. If the shaft I moves up and down angularly, the inner verticalsurfaces of the housing l8 serve as guides to limit any lateral movementof the shaft 1.

The axial thrust of the shaft I is provided for in the self-aliningbearing In at the upper end of the structure.

If so desired, means may be provided adjacent the upwardly moving fiightof the chain [1 to spray a stream of water or the like, against saidchain constantly to remove adhering grit or other foreign mattertherefrom. The means 20 preferably would comprise a nozzle connectedwith a suitable source of water under pressure not shown.

Thus it will be seen that the lower end of the shaft is hung in endlesschain I1, providing optimum operating conditions because the shaft canmove angularly within certain limits to avoid foreign objects and it mayrotate without any immediate or serious damage to any bearing surface.The housing I8 may be welded or otherwise permanently attached to theclassifier tank or it may be bolted thereto so that it is removable forinspection and service.

The lower end of the tank 5 is, of course, provided with the usual slimeoverfiow 2| and with a drain pipe connection 22.

Instead of chain l1, an endless belt, rope, cable or the like may besubstituted.

Referring to diagrammatic Figure 3, a modification of certain componentshereinbefore described is illustrated, wherein two similar groovedsheaVes Ma and Mb are substituted in place of the sheave l4, Figures 1and 2, and are similarly journalled. An endless ring or hoop 23,preferably made of steel or other suitable metal, embraces sheaves Maand Mb and carries sheave l3 and therefore represents a substitute forthe endless chain l1. 7

It is manifest that upper sheave I4, I do and I 4b are journalled onsuitable super-structure well above the level of the pool formed in thetank 5. It is obvious that the optional spraying means 29 also can beused in combination with the endless ring or hoop 23 of Figure 3.

When the endless chain H or a belt, rope or cable or the like is used,then such chain, belt, rope or cable can flex sufiiciently to permit theaforesaid upward angular movement of the lower end of the shaft I, orthe lower sheave I3 may move with reference to said chain or the like,the grooves in the sheaves l3 and M to be of suflicient depth to preventpermanent disengagement of either sheave from the chain. IT or the like.

When the ring or hoop 23 of Figure 3 is used, grooves in sheave 13, Maand Mb are provided of sufficient depth to prevent permanentdisengagement of said sheaves from said ring or hoop, if and when theshaft I and the sheave 13 move angular-1y with reference to the othercomponents.

Since it is within the scope of the present inventive concept to use achain l1 reeved over sheaves I3 and l 4, or the equivalent of said chainsuch as a cable, rope, belt or the like, the term belt as. usedhereinafter in the claims, is in,- tended tobea generic term coveringall such flexible equivalents of chain H, as well as the chain itself.

While component members l3, M, Ma and llb have been defined as sheaves,nevertheless this term used in the appended claims is definitelyintended to designate and include any type of circular track, groove,runway or the like that would be the equivalent of the sheavesillustrated, in

the function of receiving the shaft supporting element I! or itsequivalent as herein defined, or part 23 or its equivalent.

What I claim and desire to secure by Letters Patent is:

1. In classifiers of the spiral conveyor type,

an inclined tank for pulp having feed and discharge means determining aliquid level at the lower end of the tank, a rotary spiral conveyor,inclusive of a shaft, extending lengthwise of the tank, a self-aligning.bearing at the up er end of the tank in which the shaft is journalled,driving means on the tank for rotating said shaft, and a support for thelower end of said shaft comprising a chamber of slightly larger diameterthan the shaft into which the submerged end of the shaft extends forlimited lateral movement therein, a

sheave on the shaftadjacent said chamber, a

second sheave supported fro'm'the tank above its liquidlevel inalinement withsaid first mentioned sheave, and an endless member reevedover said sheaves to maintain the submerged end of the conveyor in asuspended position in the tank.

2. In classifiers of the spiral conveyor type, an inclined tank for pulphaving feed and discharge means determining a liquid-level at the lowerend of the tank, 'a rotary spiral conveyor, inclusive of a shaft,extending lengthwise of the tank, a self-aligning hearing at the upperend of the tank in which the shaft is journalled, 'driv- 3. Inclassifiers of the spiral conveyor type,

an inclined tank for pulp having feed and dis? charge means determininga liquicl level at the lower end of the tank, a rotary spiral conveyor,

inclusive of a shaft, extending lengthwise of the tank, a self-aligningbearing at theupper end of the tank inwhich theshaft is journalled,driving means on the tank for rotating said shaft, and a support for thelower end of said shaft comprising a chamber of slightly large diameterthan the shaftginto which the submerged end of the shaft'extends forlimited lateralmovement therein, a sheave on the shaft adjacent saidchamber, two coacting sheaves supported from inclusive of a shaft,extending lengthwise of the tank, a self-aligning bearing at the upperend of the tank in which the shaft is journalled, driving means on saidtank for rotating said shaft, a support for the lower end of said shaftcomprising a chamber of slightly larger diameter than the shaft intowhich the submerged end of the shaft extends for ilmited lateralmovement therein, a sheave on the shaft adjacent said chamber, a secondsheave supported from the tank above its liquid level; and an endlessmember reeved over said sheave to maintain the submerged end of theshaft in a suspended position in the tank, and. means positioned betweensaid sheaves for removing foreign matter from the ascending stretch ofsaid endless member. jj 5. In classifiers of the spiral conveyor type,

an inclined tank for pulp having feed and dis-f charge means determininga liquid level at the lower end of the tank, a rotary spiral conveyor,

inclusive of a shaft, extending lengthwise of the tank, a self-aligningbearing at the upper end of the tank inwhich the shaft is journalled,driving means on said tank for rotatingsaid shaft, a

support for the lower end of said shaft comprising a chamber of slightlylarger diameter than the shaft into which the submerged end of the Ishaft extends for limited lateral movement therein, a sheave on theshaft adjacent said chamber, a second sheave supported from the tankabove its liquid level, and an endless member reeved over said sheave tomaintain the submerged end PAUL L. WIGTONL

